This application claims the benefit of Korean Patent Application No. 2002-51604, filed Aug. 29, 2002, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to an ink cartridge, and more particularly, to an ink cartridge preventing air from flowing into a printing head chip before ink contained in the ink cartridge is used up.
2. Description of the Related Art
Generally, an ink cartridge for an inkjet printer includes a main body filled with ink. The ink in the main body is sprayed onto a paper by a predetermined amount at a time through an ink head chip provided to the main body.
FIG. 1 is a view showing the conventional ink cartridge disclosed in U.S. Pat. No. 4,771,295. Referring to FIG. 1, the conventional cartridge includes a main body 1 divided into three ink tanks. Each ink tank is provided with foam 2 made of a polyurethane material. The main body 1 is provided at a lower part thereof with an ink head chip 3 having ink spray nozzles 3a. Each ink tank inside the main body 1 is further provided at a bottom thereof with an ink pipe 4 having an ink chamber of a predetermined height in an upright position. Each ink pipe 4 is provided at an upper end thereof with a filter 5 filtering the ink to be supplied to the ink head chip 3. The ink pipe 4 and the filter 5 compress a lower portion of the foam 2 in an upward direction. Therefore, in a contact portion of the foam 2 with the ink pipe 4 and filter 5, capillary actions are increased. The foam 2 is compressed to increase density of a structure, thereby further preventing the air from moving toward the ink pipe 4.
However, the conventional ink cartridge with the above construction has to compress the lower portion of the foam 2 toward an upper end of the ink pipe 4, whereby a height of the ink pipe is increased. Thus, a distance between the foam 2 and the head chip 3 becomes longer. Therefore, a head loss (pressure loss) expressed by xe2x88x92xcfx81 gh, wherein xcfx81 g is a specific weight, and h is the height of the ink pipe 4, occurs corresponding to the height of the ink pipe 4, and thus a negative pressure in the head chip 3 is decreased. Thus, ink sprays through the head chip 3 are not performed normally, causing a print quality degradation.
An aspect of the invention is to solve the above and/or other problems and to provide an improved ink cartridge of simple construction capable of blocking air from flowing into a head chip.
Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Accordingly, an aspect of the present invention is to solve the foregoing and/or other problems by providing an ink cartridge including a main body having an ink absorbent body filled with ink, an ink head chip disposed at a lower portion of the main body to spray the ink onto a printing paper, an ink feeding pipe disposed at a lower portion inside the main body to feed the ink in the main body to the ink head chip, and a pressure rib protruding from a bottom of the main body to be higher than the ink feeding pipe to press the ink absorbent body which contacts the pressure rib before the ink feeding pipe comes in contact the ink absorbent body.
According to another aspect of the invention, the ink feeding pipe is disposed in a vertically upright position and is provided at an upper end with an ink filter.
Moreover, the main body includes a partition dividing an inside thereof into a foam chamber and an ink chamber and having a passage. The foam chamber includes the ink head chip disposed at a lower portion thereof and further includes the ink absorbent body, and the ink chamber communicates with the foam chamber through the passage and is filled with the ink.